Ab initio studies of elastic properties and electronic structures of C and BN nanotubes

The elastic properties and electronic structures of single-walled nanotubes (SWNTs) are studied using the ab initio package CRYSTAL-03. It is found that the Young modulus correlates strongly with the tubeʹs electronic structure. The study reveals that a semiconductor–metal transition can be induced by uniaxial stress for carbon nanotubes, whereas this transition is not observed for boron nitride nanotubes.